Police are treating an explosion at the Manchester Arena as a terrorist incident.
Nineteen people have died and approximately 50 were injured.
There were around 21,000 people at an Ariana Grande concert in the English city earlier today.
The explosion was heard inside the building, causing fans to flee.
It's believed to have gone off near the box office outside the arena.
Grande was not injured and tonight she tweeted her sorrow, saying she's feeling "broken".
Meanwhile, Prime Minister Justin Trudeau has tweeted that the victims and their families are in Canadians' thoughts.